Growth performance of South African Windsnyer pigs to the dietary inclusion of Amarula oil cake

Dietary effects of Sclerocarya birrea caffra seed cake replacing soyabean meal on physiology, meat and bone quality of indigenous chickens

This study investigated marula seed cake (MSC) as alternative protein source (APS) replacing soyabean meal (SBM) in indigenous chicken diets. Four hundred, 3-week-old Boschveld chicks were randomly allocated to 5 iso-energetic-nitrogenous maize and SBM-based grower diets with 0, 10, 15, 20, and 25 % MSC, each with 5 replicate pens of 16 birds, in a completely randomised design (CRD), for 9 weeks. Results showed that dietary MSC quadratically decreased bird overall feed intake (FI) (P < 0.001) and body weight gain (BWG) (P < 0.01) as it linearly decreased the weights of hot carcass (HCW; P < 0.05), spleen (P < 0.05), jejunum (P < 0.05), ileum (P < 0.001), and caecum (P < 0.001). In contrast, MSC increased chicken serum glucose (P < 0.05), cholesterol (P = 0.001) and phosphate (P < 0.05) as it decreased its amylase activity (P < 0.01). Also, it decreased bird meat lightness at 45 min (P < 0.05) and its yellowness at 45 min (P < 0.001) and 24 h (P < 0.001) whilst it increased its redness at 45 min (P < 0.01) and 24 h (P < 0.05) post-slaughter. In addition, MSC decreased chicken bone medial diaphysis (P < 0.05) as it induced no effects (P > 0.05) on overall feed conversion efficiency (FCE) and all other parameters. In conclusion, feeding of ≤ 15 % dietary MSC is nutritionally safe for indigenous chickens whilst detrimental on bird appetite, growth and meat yield, however without significantly affecting their physiology, at higher inclusion levels.

Low dietary oyster mushroom spent substrate limitedly ameliorates detrimental effects of feeding combined marula seed cake and mucuna seed meal as soya bean replacements in broiler chickens

This study investigated ameliorative effects of dietary oyster mushroom (Pleurotus ostreatus) spent substrate (OMSS) in broiler chickens fed diets supplemented with combined marula seed cake (MSC) and mucuna seed meal (MSM) replacing soya bean meal (SBM). In a completely randomised design (CRD), 400 day-old Ross 308 chicks were randomly allocated to 5 iso-nitrogenous-energetic diets (control with 100% SBM, control with 60% MSC and 40% MSM replacing SBM (MSC + MSM), MSC + MSM with 1.25% OMSS, MSC + MSM with 2.5% OMSS, and MSC + MSM with 5% OMSS) each with 8 replicate pens of 10 during starter, grower and finisher phases. Dietary MSC + MSM decreased (P < 0.001) feed intake (FI), body weight gain (BWG), and feed conversion efficiency (FCE); slaughter weight, hot carcass weight (HCW), cold carcass weight (CCW), breast weight, and back lengths (P < 0.001); serum SDMA and alanine transaminase (P < 0.05). In contrast, it increased the weights of the thigh (P < 0.001), wing (P < 0.01), liver (P < 0.001), proventriculus (P < 0.001), gizzard (P < 0.001), duodenum (P < 0.001), jejunum (P < 0.001), ileum (P < 0.001), and caecum (P < 0.01) and serum alkaline phosphatase (P < 0.05) and cholesterol (P < 0.01). Further, it increased meat redness and decreased its hue angle at 45 min post-slaughter (P < 0.01) whilst it decreased its pH (P < 0.01) and increased its shear force (P < 0.05) at 24 h post-slaughter. Compared to higher levels, low (1.25%) dietary OMSS improved, though limitedly, FI, BWG, and FCE at grower and finisher phases only (P < 0.001) whilst it reversed MSC plus MSM-induced deleterious effects on slaughter weight, HCW, and CCW (P < 0.001) and increases in gizzard weight (P < 0.001) and meat shear force at 24 h post-slaughter (P < 0.05). Otherwise, OMSS generally decreased (P < 0.05) serum SDMA and alanine transaminase whilst it abrogated and augmented increases in serum alkaline phosphatase (P < 0.05) and cholesterol (P < 0.01), respectively, and reversed the increase and decrease in meat redness (P < 0.01) and hue angle (P < 0.05), respectively. In conclusion, dietary replacement of SBM with combined MSC plus MSM induced deleterious effects in broiler chickens that were limitedly abrogated by low (1.25%) inclusion level of OMSS.

Effect of tandem repeats of antimicrobial peptide CC34 on production of target proteins and activity of Pichia pastoris

Antimicrobial peptides (AMPs) are attracting attention in the fields of medicine, food, and agriculture because of their broad-spectrum antibacterial properties, low resistance, and low-residue in the body. However, the low yield and instability of the prepared AMP drugs limit their application. In this study, we designed a tetramer of the AMP CC34, constructed and transfected two recombinant expression vectors with pGAPZαA containing a haploid CC34 and tetraploid CC34 (CC34-4js) into Pichia pastoris to explore the effect of biosynthesized peptides. The results showed that CC34 and CC34-4js expression levels were 648.2 and 1105.3 mg/L, respectively, in the fermentation supernatant of P. pastoris. The CC34-4js tetramer showed no antibacterial activity, could be cleaved to the monomer using formic acid, and the hemolytic rate of the polyploid was slightly lower than that of monomeric CC34. The average daily gain, average daily feed intake, feed conversion ratio and immune organ index of rats fed CC34 and CC34-4js showed no differences. In conclusion, CC34-4js exhibited a higher yield and lower hemolysis in P. pastoris than those of CC34. Finally, CC34 and CC34-4js enterokinase lysates showed similar antibacterial activity and both expressed peptides potentially improved the growth performance and organ indices of rats.